Effect of hoof orientation and ballast on acceleration and vibration in the hoof and distal forelimb following simulated impacts ex vivo.
Authors: McCarty C A, Thomason J J, Gordon K, Burkhart T, Bignell W
Journal: Equine veterinary journal
Summary
# Editorial Summary This 2015 biomechanical study investigated how variations in hoof-strike pattern and limb loading affect the transmission of impact forces through the distal forelimb, addressing a critical gap in understanding how ground contact might contribute to cumulative injury in the equine lower limb. Using cadaver specimens mounted on an impact-testing machine, researchers struck eight forelimbs under three different hoof-strike conditions (toe-first, flat and heel-first) at a standardised velocity of 3.55 m/s, with and without added ballast equivalent to approximately 2% body mass, whilst measuring acceleration and vibration frequencies at the hoof, first phalanx and third metacarpal using accelerometers. Heel-first landings generated significantly greater peak accelerations and higher frequency vibrations than flat or toe-first strikes; notably, adding ballast produced no measurable difference in impact transmission regardless of strike pattern, and whilst the distal structures attenuated signal energy substantially (reducing it to only 6–31% by the time it reached the third metacarpal), the energy that persisted could still pose a tissue-damaging risk. For practitioners managing performance horses or those prone to joint and bone pathology, these findings underscore the relevance of hoof-strike mechanics and foot balance to injury prevention, suggesting that gait assessment and farriery interventions targeting landing pattern may represent a valuable complement to other management strategies aimed at minimising cumulative impact loading.
Read the full abstract on PubMed
Practical Takeaways
- •Hoof-strike orientation significantly influences impact loading patterns; heel-first impacts generate the highest accelerations and may increase injury risk in predisposed horses
- •Farriers should consider hoof balance and trim to optimize strike patterns, as the distal limb structures attenuate but do not fully dissipate impact energy
- •Adding weight to the distal limb does not reduce impact shock transmission, so ballast-based interventions are unlikely to protect against impact-related injury
Key Findings
- •Heel-first strikes produced the largest peak accelerations and highest vibration frequencies compared to toe-first and flat strikes
- •Signal energy reaching the third metacarpal was only 6-31% of that measured at the hoof, demonstrating substantial attenuation by distal limb structures
- •Ballast mass (~2% body mass) had no effect on peak acceleration or vibration characteristics regardless of strike condition
- •Impact-induced vibration carries considerable energy that could be damaging to tissue and may contribute to bone injury and joint disease in the distal limb